condition mean min max ZT0-3 23.995359999999998 23.995359999999998 23.995359999999998 ZT4-7 27.46223 27.46223 27.46223 ZT8-11 23.76031 23.76031 23.76031 ZT12-15 23.830740000000002 23.830740000000002 23.830740000000002 ZT16-19 33.465403333333335 33.465403333333335 33.465403333333335 ZT20-23 47.1319 47.1319 47.1319